Method and apparatus for the continuous ringless spinning of yarn from separated staple fibers in a rotating spinning chamber



April 29, 1969 J. STARY ET AL 3,440,812

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METHOD AND AFPA FOR THE CONTINUOUS RINGLESS SPINNING OF YARN OM SEPARATED STAPLE FIBERS IN A ROTATING SPINNING CHAMBER Filed Oct. 9, 1957 Sheet of 4 I r A 5 x H (ZI 16' A ril 29, 1969 J. STARY ET AL 3,440,81 2 METHOD AND AFPARATUS FOR THE CONTIN S RING S SPINNING 'OF YARN F LE FIB IN A ROTAT UOU ROM SEPARATED STAP ING SPINNING CHAMBER Filed Oct. 9, 1967 Sheet 3 of 4 Ap-l 29, 1969 J. STARY ET AL 3,440,8l2

METHOD AND APPARATUS FOR THE CONTINUOUS RINGL S SPINNING OF' YARN FROM SEPARATED STAPLE FIB IN A ROTATING SPINNING CHAMBER Filed Oct. 9. 1967 Sheet I// ///////////////VV & 4

Ap'l 29, 1969 J STARY ET AL 3,440,812

METHOD AND APPARATUS IMB 'NIE GONTINUOUS RINGLESS SPINNING OF YARN FROM SEPARATED STAPLE FIBERS IN A ROTATING SPINNING CHAMBER Filed oot. 9, 1967 Sheet 4 of 4 United States Patent O 6 Int. c. o 7/00, 7/76 U.S. Cl. 57--58.89 10 Claims ABSTRACT OF THE DISCLOSURE A method of continuous ringless spinning of yarn in which a portion of the yarn adjacent the fiber collecting surface of a rotating spinning chamber and spaced from the inner end of the withdrawing passage of the yarn is frictionally engaged by a surface portion of the rotating spinning chamber and preferably deflected in direction of the axs of rotaton of the latter to apply a frictional force to the aforementioned yarn portion, and an apparatus for carrying out the method.

Background of the invention The present invention relates to a method and apparatus for the continuous ringless spinning of yarn in a rotating spinning chamber in which separated staple fibers are deposited on the so-called collecting surface of the spinning chamber and withdrawn in the form of a yarn through a withdrawing passage of the apparatus.

Spinning chambers are known in which the separated staple fibers are fed by means of air currents into the spinning chamber so that the staple fibers are deposited in form of a ribbon on the so-called collecting surface of the spinning chamber. The yarn end adjacent to the collecting surface collects, while the yarn is withdrawn through the withdrawing passage, fibers from the ribbon while imparting a twist thereto so that the fibers are continuously twisted into a yarn. The yarn is withdrawn through the socalled funnel and wound onto a bobbin. During the aforementioned process, the collecting point, i.e., the point of collecting the fibers from the ribbon by the twisting end of the yarn, moves in a direction corresponding to the rotary motion of the spinning chamber at a speed which equals the sum of the speed of the collecting surface of the spinning chamber and the withdrawal speed of the yarn. The yarn in the spinning chamber has in an aXial View a form which is arcuately bent between the collecting point and the withdrawal passage in the direction of the rotary motion of the spinning chamber.

During the spinning of fibers in such a spinning chamber it happens sometimes that shells or other impurities contained in the raw material or fiber agglomerates which have not been properly separated are fed together with the separated fibers into the spinning chamber. When such impurities or shells fall onto the collecting surface of the spinning chamber, a localized portion of greater mass will form in the ribbon and when this greater mass begins to be withdrawn by the yarn, the increased centrifugal force of this greater mass will produce a considerably increased lifting resistance and therewith an increased tension in the yarn. If no breakage takes place in this case, the increased Patented Apr. 29, 1969 ice resistance will cause on the one hand a change in the shape of the yarn section in the spinning chamber in such a manner that the yarn will now curve from the collecting point towards the withdrawal passage in a direction opposite to the direction of rotaton of the spinning chamber, and on the other hand a change of the relative speed of the collecting point on the collecting surface, which change of speed will be equal to the difference in the rotary speed of the collecting surface and the withdrawing speed of the yarn.

If the above-mentioned situation occurs, the penetration of twist in the yarn up to the collecting point is much more diflicult to obtain due to the mentioned unsuitable configuration of the yarn end in the spinning chamber, and this causes a considerable drop in the strength of the yarn which is spun, which in turn will increase the number of yarn breakages during the spinning process.

The above drawbacks will detrmentally effect the spinning process especially during the spinning of fine yarns, or when the yarn is withdrawn at a high speed, and particularly during spinning of low twisted yarns.

A spinning chamber is known in which the collecting surface is provided with needles for controlling the shape of the yarn curve in the spinning chamber. The action of these needles on the ribbon of fibers which is spun into the yarn is however so intensive that when fine yarns are spun, the holding force exerted by the needles on the fiber ribbon is sometimes greater than the tensile strength of the yarn which is spun so that yarn breakage will frequently occur. This yarn breakage increases when the number of revolutions of the spinning chamber is increased so that this known construction will not be suitable for spinning fine yarns and also not be suitable to a high speed spinning process.

In addition, impurities contained in the fed raw material adhere, as known, to the collecting surface of the spinning chamber and must be removed from time to time. Evidently, when the collecting surface is provided with needles, this cleaning process is rendered much more difficult.

It is an object of the present invention to overcome the aforementioned drawbacks in spinning chambers for the continuous spinning of yarn.

It is a further object of the present invention to provide a method and apparatus for the continuous ringless spinning of yarn in which also fine yarn numbers may be produced with considerable speed without the danger of frequent yarn breakagcs during the spinning process.

Summary of the invention With these objects in view, the method according to the present invention of continuous ringless spinning of yarn in a spinning chamber comprises the steps of depositing separated staple fibers on the annular collecting surface of a spinning chamber, spinning the fibers into yarn while rotating the spinning chamber about its axis and withdrawing the yarn from the collecting surface and out of the spinning chamber through an opening coaxial with the aforernentioned axis, and frictionally engaging a portion of the yarn adjacent the collecting surface and spaced from the aforementioned opening with a surface portion of the rotating spinning chamber to apply to the yarn portion a frictional force rotating with the spinning chamber. Preferably the aforementioned yarn portion is axially deflected by the surface portion of the spinning chamber to thereby increase the frictional force applied to the yarn portion.

The spinning apparatus according to the present invention for carrying out the aforementioned method may comprise a rotary spinning chamber having an axis of rotation and a coaxial annular collecting surface for fibers to be spun into a yarn, means for depositing fibers onto the collecting surface, a coaxial withdrawing passage having an inner end axially displaced from the collecting surface, means for withdrawing the yarn from the collecting surface through the aforementioned withdrawing passage, and means forming part of and rotating with said spinning chamber and frictionally engagng a yarn portion adjacent to the collecting surface and spaced from the withdrawing passage for applying a frictional force to the aforementioned yarn portion. Preferably, the last mentioned means for applying a frictional force to the aforementioned yarn portion is arranged to deflect the yarn portion in aXial direction to thereby increase the frictional force.

The engaging and deflectng means is preferably in the form of an annular deflecting surface coaxially arranged with the axis of rotition of the spinning chamber and extending inwardly from the collecting surface. The annular deflecting surface may `be in the form of a substantially frusto-conical surface and preferably the inner edge of said frusto-conical surface projects beyond a straight line extending from the collecting :surface to the inner end of the withdrawal passage to thereby deflect the yarn portion adjacent to the collecting surface in direction of the axis of the spinning chamber so as to increase the friction imparted to this yarn portion.

The spinning chamber -may have an end wall and a peripheral wall having an inner substantally frustoconical surface tapering in a direction away from the end wall, and the frusto-conical deflectng surface may be constituted by an annular surface portion of the end wall inclined to the inner frusto-conical surface of the peripheral wall and joined to the latter by an annular groove forming the collecting surface. Advantageously, this annular groove which forms the collecting surface has in a plane including the axis of rotation of the spinning chamber a radius of curvature between 0.28 and 0.32 mm. which permits spinning of the most current yarn numbers.

To achieve good results with the spinning chamber according to the present invention, half of the apex angle of the frusto-conical deflecting surface is smaller than the angle included between the axis of rotation and a straight line in a plane including the aforementioned axis and passing from the inner edge of the frusto-conical deflecting surface to the inner end of the withdrawal passage.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its Construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

Brief descriptions of the drawings FIG. l is a schematic aXially cross section of a spinning chamber according to the present invention;

FIG 2 is a partial axial cross section of an apparatus similar to FIG. 1 and illustrating the angles which the defiected portion of the yarn and the remaining yarn portion respectively include with the axis of rotation of the spinning chamber;

FIG. 3 is an aXial cross section of a modified embodiment according to the present invention in which feeding of the fibers into the spinning chamber and withdrawal of the spun yarn from the spinning chamber is made in opposite directions;

FIG. 4 is a parlial axial cross section of a spinning chamber according to the present invention and showing 4 a form of a spinning chamber slightly deviating frorn that shown in FIG. 1;

FIG. 5 is a partial cross sectional View, drawn to an enlarged scale, of the groove-shaped collecting surface of the spinning chamber; and

FIG. 6 is a cross sectional View taken along the line 6-6 of FIG. l and illustrating especially the configuration of the yarn between the collecting point and the withdrawing passage.

Descripton of the Preferred embodments Referring now to the drawings and more specifically to FIG. 1 of the same, it will be seen that the spinning chamber 1 according to the present invention may be provided in its 'bottom wall 19 with a plurality of substantally radially extending ventilating passages 2 which during fast rotation of the spinning chamber about its axis will provide an underpressure in the interior of the spinning chamber. A shaft 3 integral with the bottom wall 19 projects downwardly therefrom and is rotatably mounted in bearings 4 and 5 supported in any suitable manner on the partially illustrated machine frame 6. The shaft 3 is provided intermediate the bearings 4 and 5 with a pulley portion 7 engaged by a belt 8 for rotating the shaft 3 and therewith the spinning chamber about the axis of the latter. The spinning chamber has an annular peripheral wall which preferably has an inner surface 13 in form of a frusto-conical surface tapering in a direction away from the bottom wall 19 of the spinning chamber. The upper open end of the spinning chamber 1 is substantally closed by a lid 9 mounted on the machine frame 6 and slightly spaced from the upper end of the peripheral wall of the spinning chamber so as to be out of contact with the latter and so that the spinning chamber may rotate freely with respect to the stationary lid 9. An inlet passage 10 extends from a known separating device 12, schematically illustrated in FIG. 1, and which separates fibers from a fiber body 25, through an appropriate opening in the lid 9 into the interior of the spinning chamber for feeding separated fibers 11 into the interior of the spinning chamber. The inner portion of the inlet passage 10 is bent towards the inner surface 13 of the peripheral wall of the spinning chamber. A tube portion 15 constituting a withdrawal passage for the yarn to be spun in the spinning chamber is fixed in the lid coaxially with the axis of rotation of the spinning chamber. A pair of oppositely rotated withdrawing rollers 16 are located above the tube 15 frictionally engaging the yarn 18 on opposite sides for withdrawing the same through the withdrawal passage, and the yarn is subscquently wound on a bobbin 17 located above the withdrawing rollers.

The bottom wall 19 of the spinning chamber is made in such a way to form a deflecting element which in the embodiment as shown in FIG. 1 has the shape of a concentric projection 20 having an outer substantally frusto-conical defiecting surface 201 inclined to the inner frusto-conical surface 13 of the peripheral wall of the spinning chamber and joined to the latter by an 'annular groove 14 forming a collecting surface on which the separated fibers emanating from the inlet passage 10 will collect. The :bottom 19 forms inwardly of the projection 20 a recess 22 from which the aforementioned ventilating passages 2 eXtend in substantally radial direction to the outer surface of the spinning chamber.

As shown in FIG. 2, the inner edge of the collecting surface 201 projects in axial direction beyond a theoretical line 1 connecting the bottom of the groove-shaped collecting surface 14 with the inner end of the tube 15 constituting the widthdrawing passage. As lkewise shown in FIG. 2, the angle A, which is half of the apex angle of the defiecting surface 201 is smaller than the angle B included between the axis of rotation 24 of the spinning chamber and a straight line in a plane including this axis and passing from the inner edge 141 of the deflectng surface 201 at which the yarn 18 will get out of contact with the defiecting surface to the inner end 21 of the tube or withdrawing passage 15. The arrangement is made preferably in such a way to establish a ratio between the angle A and B within the range 1:1.01 and 1:9` and preferably within a range 1:1.2.

The apparatus as described above in connection with FIG. l will operate as follows:

The fibers 11 separated by the separating device 12 from the fiber body 25 are fed through the inlet passage by the action of the partial vacuum produced in the interior of the spinning chamber during fast rotation of the latter by the ventilating passages 2 into the interior of the spinning chamber 1 and slide downwardly at the inner surface 13 of the peripheral wall of the spinning chamber toward the collecting surface 14 on which the fibers are deposited in form of a ribbon 26. Yarn 18 is initially fed through the withdrawing channel 15 into the spinning chamber to engage with its end the ribbon 26 which begins to accumulate on the end of the inserted yarn, upon which the direction of movement of the yarn 18 is reversed and the yarn is spun in and continuously withdrawn by the withdrawing rollers 16 and wound onto the bobbin. During spinning, the front end of the yarn thus formed moves along the collecting surface 14 in the same direction as the spinning chamber rotates at a speed equal to the sum of the speed of the collecting surface and the withdrawal speed of yarn 18 and the yarn end gathers at a point 23 (FIG. 6) also called collecting point the fibers from the ribbon 26 simultaneously imparting a twist thereto so as to spin the same into a yarn. In order to avoid a change of the direction of movement of the collecting point due to a sudden increase of the centrifugal forces acting at the collecting point of the ribbon when heavy impurities or fiber agglomerates are fed together with the separated fibers into the spinning chamber, the yarn 18 is subjected at a portion adjacent the collecting surface 14 and spaced from the withdrawing passage 15 to the frictional eifect of the deflecting surface 201 which deflects the portion 18 of the yarn engaging the defiecting surface in axial direction and simultaneously entrains it in the direction of rotation of the spinning chamber, preventing thereby a change in the direction of movement of the collecting point 23 and thus the production of a yarn of inferior quality or eventual yarn breakage.

The embodiment shown in FIG. 3 dilfers from the embodiment as shown in FIG. 1 and above-described mainly in that the feeding of the separated fibers into the spinning chamber 1 is performed from one side, whereas the withdrawal of yarn from the interior of the spinning chamber is performed from the other side of the latter. In this case, the tube 15 forming the withdrawing passage extends through an axial bore of the shaft 3 out of contact with the inner bore surface.

The embodiment shown in FIG. 4 diifers slightly from the embodiment shown in FIG. l in that the central depression 19' in the bottom wall of the spinning chamber dose not extend from the inner edge 2 6 of the defiecting surface 201, but in this case the top face 191 of the bottom wall of the spinning chamber 1 extends in a plane normal to the axis of rotation of the spinning chamber inwardly from the annular edge 28 of the defiecting surface 201 and the depression 19 extends from this top surface 191 downwardly into the bottom wall of the spinning chamber only into a central portion of the bottom wall.

The groove-shaped collecting surface 14 has in a plane including the axis of rotation of the spinning chamber a radius of curvature R which is preferably in the range of 0.28 to 0.32 mm. Such a dimension will be suitable for the spinning of most current yarn numbers Without the necessity of changing the dimension of the collecting surface.

It will be understood that each of the elements described above, or two or more together, may also find a usefull application in other types of apparatus and method for the continuous ringless spinning of yarn in a rotating spinning chamber diifering from the types described above.

While the invention has been illustrated and described as embodied in an apparatus for the continuous ringless spinning of yarn in a spinning chamber provided with a spinning chamber has an end Wall and a peripheral wall defiecting surface frictionally engaging the yarn at a portion thereof adjacent to the collecting surface of the spinning chamber, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

We claim:

1. A method of continuous ringless spinning of yarn in a spinning chamber rotatable about an axis and having an annular coaxial collecting surface, comprising the steps of depositing separated staple fibers on said collecting surface; spinning said fibers into a yarn While rotating the spinning chamber about said axis and withdrawing the yarn from said collecting surface and out of said spinning chamber through an opening coaxial with said axis; and frictionally engagng a portion of said yarn adjacent said collecting surface and spaced from said opening with a surface portion of said rotating spinning chamber to apply to said portion of said yarn a frictional force entraining said yarn portion in the direction of rotation of the spinning chamber.

2. A method as defined in claim 1 and including the step of axially defiecting said portion of said yarn by said surface portion to increase the frictional force applied to said yarn portion.

3. A spinning apparatus comprising, in combination, a rotary spinning chamber having an axis of rotation and a coaxial annular collecting surface for fibers to be spun into a yarn; means for depositing fibers onto said collecting surface; a coaxial withdrawing passage having an inner end axially displaced from said collecting surface; means for withdrawing the yarn from the collecting surface through said withdrawing passage; and means forming part of and rotating with the spinning chamber and frictionally engaging a yarn portion adjacent said collecting surface and spaced from said withdrawing passage for applying a frictional force to said yarn portion.

4. A spinning apparatus as defined in claim 3, wherein said means for applying a frictional force to said yarn portion is arranged to deflect said yarn portion in axial direction.

5. A spinning apparatus as defined in claim 4, wherein said engaging and defiecting means is in the form of an annular defiecting surface coaxially with said axis and extending inwardly from said collecting surface.

6. An apparatus as defined in claim 5, wherein said annular defiecting surface is a substantially frusto-conical surface.

7. An apparatus as defined in claim 6, where half of the apex angle of said frusto-conical defiecting surface is smaller than the angle included between said axis of rotation and a theoretical straight line in a plane including said axis and passing from the inner edge of said frustoconical defiecting surface to said inner end of said withdrawing passage.

8. An apparatus as defined in claim 6, wherein the inner edge of said annular defiecting surface projects in direction of said axis beyond a theoretical straight line extending from said collecting surface to said inner end of said withdrawing passage.

9. An apparatus as defined in claim 8, wherein said spinning chamber has an end wall and a peripheral wall having an inner substantally frusto-conical surface tapering in a direction away from said end Wall, and wherein said frusto-conical deflecting surface is a surface portion of the end wall inclined to said inner frusto-conical surface and joined to the latter by an annular groove forming said collecting surface.

10. An apparatus as defined in claim 9, wherein said annular groove has in a plane including said aXis a radius of curvature between 0.28 and 0.32 mm.

References Cited UNITED STATES PATENTS JOHN PETRAKES, P''ma'y Examer.

U.S. Cl. X.R. 

